Answer:
9 square root of 7
Step-by-step explanation:
You’re going to break apart radical 28 into square root of 4 and square root of 7.
The square root of 4 is 2 so you add the 2 to the 3 and it equals 5 and since the square root of 7 can’t be simplified and it stays the same. So all you do is add 4 radical 7 and 5 radical 7 which equals 9 radical 7.
Radical- is square root sign
Answer: 0.4693877
Step-by-step explanation:
Given that:
cos x=−6/7,
From trigonometry :
Cosx + sinx = 1
Cos2x = cos(x + x)
Recall the double angle identity:
Cos2x = 2cos^2x - 1
Sin2x = 1 - 2sin^2x
Since cosx = - 6/7
Then
Cos2x = 2cos^2x - 1
Cos2x = 2cosx^2 - 1
Cos2x = 2(-6/7)^2 - 1
Cos2x = 2(36/49) - 1
Cos2x = 2 * (72/98) - 1
Cos2x = (2 * 0.7346938) - 1
Cos 2x = ( 1.4693877 - 1)
Cos2x = 0.4693877
Answer:
x ≈ 21.7
I rounded to the nearest tenth because the values are given in tenths. The first few digits of x are below if you are rounding to something else, as the image is cut out.
Step-by-step explanation:
(It will not let me post, so I've attached a screenshot of my explanation:)

Multiply both sides of the equation by 12
